Batch centrifuges are commonly employed in sugar processing for separating sugar crystals from massecuite. During such separation, an amount of massecuite is placed in a centrifuge basket. The basket is then accelerated to a predetermined angular velocity which is maintained for a predetermined spin time. As the basket spins, liquid in the massecuite is forced through a cylindrical filter screen that covers an interior sidewall of the basket while sugar crystals are retained by the filter screen. The separated liquid is flushed through perforations in the centrifuge basket. After the spin is completed, a scraper arm is used to remove the sugar crystals from the filter screen. The sugar crystals are then collected through a hole in the bottom of the basket.
Filter screens of batch centrifuges typically experience a significant amount of wear during operation, such as may result from engagement with abrasive sugar crystals and from engagement with scraper arms. It is therefore necessary to replace the filter screens of batch centrifuges on a periodic basis. Since the interiors of batch centrifuges are generally only accessible through openings that are significantly smaller than a typical filter screen, filter screens are often constructed from very thin foils or meshes that allow the filter screen to be folded or collapsed upon itself and passed through a small opening in a centrifuge before being unfurled and installed within the centrifuge. However, because they are so thin, such foils and meshes lack durability and must be replaced more often than is desirable. In addition, due to the relatively fragile construction of such foils and meshes, heavy cylindrical mesh backings are typically between the filter screen and the centrifuge wall to provide thin filter screens with additional support. These mesh backings are typically in the form of thick, heavy chain-like structures. Such mesh backings, however, add weight and cost and the additional weight may impede the functioning if the centrifuge. Although use of filter screens formed of thicker, more durable foils and meshes may be advantageous, they have not been used in centrifuge applications because, due to their rigidity, they cannot be collapsed to fit through the opening in the top of the centrifuge. Their use requires the centrifuge to be disassembled to insert, remove or replace the filter screen. Furthermore, any blockage or damage caused during operation would require the entire foil to be replaced, adding cost and time consumption.
In view of the forgoing, it would be advantageous to provide a durable batch centrifuge filter screen that can be conveniently and expeditiously removed and replaced.